The root of the war was a Turkish decision to take back lands allotted to Armenia in the Treaty of Sevres which the Allies had negotiated with the Ottoman Empire but which the Turkish rebels, who had displaced the Ottoman government, did not recognize. They correctly gambled that the Allies would not intervene on Armenia's behalf and commenced an invasion of Armenia on September 13, which should be regarded as the real beginning of the war. On this date Armenia declared war on Turkey and commenced offensive actions, which worked at first.
The war soon went badly and the Armenians were forced to accept an armistice on November 18, 1920. The Soviets then invaded on November 29, 1920, effectively putting an end to the country. A peace treaty by the new government, essentially a treaty between the USSR and the Turkish rebels, was concluded on December 2, 1920.
The early 20th Century was one disaster after another for the Armenian people. The Ottoman government killed over 1,000,000 Armenians during World War One and the Turkish rebels committed further atrocities upon Armenian civilians as it entered the country. The country regained its independence on September 21, 1991.
